Thermal-insulation fabric and method of making the same



Feb. 22, 1955 J, 5. CARTER 2,702,463

THERMAL-INSULATION FABRIC AND METHOD OF MAKING THE SAME Filed'May 3, 1951 2 Sheets-Sheet 1 /l I I INVENTOR. T055 6 S. (if/E Y a M MCn-L Miran/s26 Feb. 22, 1955 J. 5. CARTER 2,702,463

THERMAL-INSULATION FABRIC AND METHOD OF MAKING THE SAME Filed May 5, 1951 2 Sheets-Sheet 2 1 LJ X/O Ill I United States Patent THERMAL-INSULATION FABRIC AND METHOD OF MAKING THE SAME Joseph S. Carter, Hartford, Conn., assignor, by mesne assignments, to Roosevelt Mills, Inc., New York, N. Y., a corporation of New York Application May 3, 1951, Serial No. 224,315

25 Claims. (Cl. 66--190) This invention relates to thermal insulation fabrics and a method of and apparatus for making the same.

One object of the present invention is the provision of a flexible fabric having improved heat insulating properties and capable of being manufactured in quantity and at comparatively low cost.

Another object of the present invention is the provision of an improved composite fabric having air pockets, which is economical to manufacture, extremely flexible and strong, and which possesses unusual insulating properties thereby providing a fabric having a multitude of uses in wearing apparel, sleeping bags, blankets and in various other applications.

Another object is the provision of an improved composite fabric comprising two layers of fabric and interposed lengths of yarn secured together by connecting the outer layers to each other and to the intermediary yarn along lines extending transversely of said lengths of yarn.

Another object of the present invention is the provision of a composite fabric comprising two layers of fabric having therebetween an intermediary yarn secured together at spaced portions and with the intermediary yarn being more shrinkable than the outer layers to produce a puckered or wrinkled composite fabric.

Another object of the present invention is the provision of a composite fabric comprising two layers of knit fabric having disposed therebetween an intermediary yarn with the said yarn interknit with the two layers at spaced Wales.

Another object of the present invention is the provision of an improved composite fabric having incorporated therein a metallic yarn or highly flexible wire which can be connected to a suitable source of electricity for heating purposes.

Another object of the present invention is the provision of an improved method of making a composite knit fabric of the character described on a conventional circular or flat knitting machine, with simple attachments to or adaptations of parts of the machine.

Yet a further object of the present invention is the provision of improved apparatus for directing the feed of additional yarn for interposition between spaced layers in the formation of a composite knit fabric.

The above and other objects, features and advantages of the present invention will be more fully understood from the following description considered in connection with the accompanying drawings.

In the drawings:

Fig. 1 is a diagrammatic back view, on an enlarged scale, of fabric made according to the present invention taken at the area encircled at E in Fig. 4;

P Fig. 2 is a sectional view taken on the line 22 of Fig. 3 is a sectional view taken on the line 33 of Fig. 1;

Fig. 4 is a fragmentary plan view of a piece of fabric made according to the present invention with a part of one layer folded over to reveal the intermediate layer;

Fig. 5 is a fragmentary plan view of a piece of fabric made according to the present invention after shrinkage where the intermediate layer has different shrinkage properties than the outer fabric layers;

Fig. 6 is a fragmentary perspective view of part of a circular knitting machine, with parts omitted, showing the activation of one cylinder needle and certain of the dial needles for interknitting intermediate layers along 2,702,463 Patented Feb. 22, 1955 the wales and showing the special feed for the intermediate yarn.

Fig. 7 is a fragmentary perspective showing the relation of intermediate layer yarn and yarns of the fabric layers to a cylinder needle for the tie-in of said yarns walewise of the fabric during the knitting thereof; and

Fig. 8 is a view similar to Fig. 3 showing a modified form of the present invention.

The composite knit fabric 10 embodying the present invention comprises two layers 12 and 14 of knit fabric disposed in face-to-face relation with a plurality of lengths of yarn 16 interposed between the layers 12 and 14, said lengths of yarn 16 being preferably coextensive with the length of the fabric 10 although, if desired, the lengths of yarn 16 may be shorter than the fabric 10. The yarn 16 is preferably soft and pliable, as are the layers 12 and 14, and is preferably thicker than the knit yarn of said layers and has little or no twist, although the invention is not narrowly circumscribed by these characteristics of the yarn. The lengths of interposed yarn 16 extend longitudinally of and between the courses of the outer layers and transversely of the spaced wales, in relationship to the layers 12 and 14. The layers 12 and 14 are interknit along the laterally spaced courses 18 and also along the laterally spaced wales 20 to form the pockets 22. Thus it will be seen that the pockets 22 are defined at two side edges 24 thereof by portions of the interknit courses 18 and at the two side edges 26 at right angles to the edges 24 by portions of the laterally spaced interknit wales 20. The intermediate yarn 16 which extends longitudinally of and between the courses of the fabric layers 12 and 14 have portions disposed in the pockets 22, as shown in Fig. 4. Said intermediate yarn 16 is disposed between series of loops of the courses of the two layers 12 and 14 and each of the lengths of yarn has longitudinally spaced portions interknit with certain of the loops of the wales of layers 12 and 14 as will be described in detail hereinafter. For the sake of clarity, the layer 12 will be referred to as the outside layer whereas the layer 14 will be referred to as the inside layer hereinafter.

It will be readily understood that when the fabric is knit on a circular knitting machine having cylinder needles and dial needles, the fabric will be tubular and the layers will be separate except at the points or lines at which both the dial and cylinder needles are activated at the same time for interknitting the yarn of layer 12 with loops of layer 14. The machine 11 is of the multi-feed type with layer 12 being knit by the activation of the cylinder needles 44 and the layer 14 being knit by the activation of the dial needles 46, the simultaneous actuation of said needles effecting the horizontal interknit 18 between the layers, as is well known in the art. When a flat fabric is desired, the tubular fabric can be cut, or if preferred the fabric can be formed on a fiat bed knitting machine with two needle beds, as will be understood.

With reference to Figs. 1 to 3, the outside layer 12 comprises a plurality of integral loops or stitches 28 and the inside layer 14 comprises a plurality of similar loops or stitches 30 as will be apparent to those skilled in the art. The layers 12 and 14 are secured together at spaced intervals throughout the fabric by knitting a loop of one web through a loop of the other web, as shown in the illustrated embodiment, the loop 32 of the layer 12 being interknit with the loop 34 of layer 14. Thus a loop or stitch 32 of layer 12 is drawn through a loop or stitch 34 of layer 14, thereby tying the two webs 12 and 14 together by the spaced loops 32 as clearly illustrated in Fig. l, and as will be apparent to those skilled in the art. By interknitting layers 12 and 14 along continuous spaced horizontal lines or courses 18, which is accomplished by interknitting layers 12 and 14 along preselected courses by means of the loops 32 as above described, edges 24 of the pockets 22 are thereby formed, as will be readily understood. In the illustrated embodiment, the intermediate yarn 16 is interknit with layers 12 and 14 at the spaced wales 20 which form the edges 26 of the pockets 22. To accomplish the interknitting of the outside layer 12, inside layer 14 and the intermediate yarn 16, a loop 40 of the intermediate yarn 16 is interknit with a loop 38 of the outside layer 12 and with a loop 36 of the inside layer 14 as clearly shown in Fig. 1 which is a view looking at the back of the fabric. It will be seen that the interknitting of the loops 36, 38 and 40 secure or interknit the fabric layers 12 and 14 and the yarn 16 of which the loops are an integral part. The interknitting of the layers 12 and 14 and the yarn 16 at the spaced wales 20 is effected by the additional actuation of the cylinder needles 52 at spaced intervals in a manner to be described hereinafter. It will be readily apparent that by interknitting the intermediate yarn 16 with the fabric layers 12 and 14 at predetermined spaced Wales, a composite fabric will result having pocket formations 22. Thus in the preferred embodiment the interknitting of the loops 36, 38 and 40 takes place along spaced wales although it will be readily apparent that the intermediate yarn 16 may have longitudinally spaced portions interknit with any of the loops of the courses of the two layers 12 and 14 in any predetermined arrangement. The multiplicity of pockets 22 defined by the laterally spaced courses 18 and the laterally spaced wales 20 have opposite sides of knit fabric which are free from direct connection to each other except at the above described spaced interknit courses 18 and spaced interknit wales 20. The intermediate yarn 16 which is interposed between the sides of the pockets 22 formed in the layers 12 and 14 lies between the interknit courses 18 but is secured against longitudinal displacement by virtue of its being interknit at the spaced wales 20. Although the above invention has been described in reference to a knit fabric, certain aspects of the invention may be applied to woven fabrics.

To produce a puckered or wrinkled composite knit fabric, a segment which is indicated at 42 as shown in Fig. 5, an inherently more shrinkable intermediate yarn 16 than the yarn comprising layers 12 and 14, or at least one of them, is interposed between the layers 12 and 14 and the composite fabric 10 is wetted for shrinking the same forming a composite fabric segment 42. It will be readily understood that the degree of puckering or wrinkling of the fabric segment 42 will be dependent on the relative shrinking properties of the fabric layers of which it is composed, the greater shrinkage of the interposed yarn 16 relative to the layers 12 and 14 resulting in a fabric segment 42 having a high degree of puckering or wrinkling. It will be apparent that when the lengths of floated-in yarn 16 are inherently more shrinkable than the layers 12 and 14 the lengths of yarn 16 will shrink in the direction of the courses 18 when the composite fabric 10 is wetted or otherwise treated for shrinking the same, the opposite sides of the pockets 22 will be accordingly puckered to form air pockets. It is to be understood that the fibers used in either of the layers 12 and 14 and in the intermediary yarn 16 may be of any fabric material and it is mentioned by way of example and not by way of limitation wool, cotton, rayon or nylon may be used in any combination. If desired the intermediate layer 16 may be composed of shrink-resistant wool or wool of a predetermined or controlled shrinkage and layers 12 and 14 may be composed of yarn which will shrink less than the yarn of the intermediate layer whereby the resultant fabric will shrink to the extent of the shrinkability of its component fibers, thus producing a fabric which will not shrink beyond a given point after the shrink treatment. The pockets 22 may be puckered to a greater extent by increasing the tension on the intermediate yarn 16 while layers 12 and 14 are knit normally, thereby increasing the air space in said pockets to decrease the thermal conductivity of the fabric without increasing the weight of the fabric. The above described fabric will be very flexible in both a vertical and horizontal plane to any desired extent depending on the yarns selected for the various layers. The fabric can be constructed to have all the flexibility and resiliency of a knitted fabric with less weight and bulk for a given amount of insulating properties, as compared to other fabrics. The thermal conductivity of the composite fabric may be varied within a wide range by the selection of the layers or any combination of layers comprising the composite fabric.

In the manufacture of the composite knit fabric 10 the two layers 12 and 14 are knitted simultaneously in faceto-face relation and the loops of said two layers are inter knit along spaced courses and along spaced wales to form a multiplicity of pockets 22. Lengths of yarn 16 are interposed between the layers 12 and 14 in intermediate relation to a plurality of successive wales simultaneously with the knitting of the two layers and the interknitting of the two layers resulting in the yarn 16 being simultaneously interknit with the fabric layers 12 and 14 at the spaced wales, as will be readily understood. The above method is readily carried out on a circular knitting machine with minor structural additions or adaptations as will be described hereinafter, but it is to be understood that the invention is not limited to a circular knitting machine or circular or tubular layers made on such a knitting machine. With reference to Fig. 6, the layer 12 is knit by the cylinder needles 44 and the layer 14 is knit by the dial needles 46, it being understood that, except when the layers are interknit, when the cylinder needles 44 are activated the dial needles 46 remain in active and when the dial needles 46 are activated the cylinder needles 44 remain inactive. As will be clear to those skilled in the art, the horizontal interknit 18 between the layers 12 and 14 is accomplished by actuating both the cylinder needles 44 and dial needles 46 simultaneously so that yarn is delivered to both said dial and cylinder needles when they are in knitting position. In the illustrated embodiment the cylinder 48 is stationary while the needle actuating cam (not shown) rotates, and the yarn feed 50 rotates with the cam, although it will be readily apparent that the reverse situation or any other suitable arrangement could be utilized as will be readily apparent to those skilled in the art. Although only one yarn feed is illustrated at 50, it will be understood that as in the usual conventional circular knitting machine of the type referred to there are a plurality of yarn feeds which supply yarn to the dial needles and a plurality of yarn feeds which supply yarn to the cylinder needles, said yarn feeds being disposed in circumferentially spaced relation, there being a dial needle yarn feed positioned between two cylinder needle yarn feeds and vice versa so that said yarn feeds for the dial and cylinder needles respectively alternate around the machine. As this is a well known conventional arrangement in circular knitting machines further description and illustration thereof is considered unnecessary. It will be noted however that in Fig. 6 the yarn guide 50 is illustrative of one of the yarn guides for the dial needles. The vertical interknit 20 of the layers 12 and 14 and the intermediate yarn 16 is accomplished by having one cylinder needle 52 activated and knit on the feed that knits in the dial. More particularly, with reference to Fig. 7, before the rib stitch at wale 20 is completed and while the latch of cylinder needle 52 is open with the latter being in a raised position, yarn 16 is laid across the open latch of said needle below the dial needle level (see Fig. 6). Thus when the needle 52 is in the position shown in Fig. 7 yarn 16 is positioned across the open latch and yarn of layer 12 is positioned under the hook of said needle, it being noted that yarn of layer 14 will be disposed under the latch of said needle from the previous feed. When needle 52 is lowered for the casting-off operation, the needle latch will be closed and the yarn of layer 14 slips over the yarn of layer 12 and yarn 16 to form a loop and to interconnect with the loops of the yarn of layer 12 and yarn 16 to form wale 20 made up of yarns of layers 12 and 14 and yarn 16. When knitting outside of the wales 20, the yarn of layer 14 is drawn to the back of the fabric and the yarn of layer 12 is drawn to the front thereof, it being noted that all of the yarns of layers 12 and 14 and yarn 16 are drawn to the front of the fabric at wale 20. Thus, the fabric layers 12 and 14 are periodically interknit along spaced wales and the intermediate yarn 16 is interposed between said layers in intermediate relation to a plurality of successive wales 20 simultaneously with the interknitting of the two layers 12 and 14 so that the intermediate yarn 16 is simultaneously interknit with said fabric layers at the spaced wales 20. Although in Fig. 6 a single cylinder needl 52 is shown as being activated by suitable mechanism it will be readily understood that any number of cylinder needles and at any desired spacing may be activated depending on the spacing desired between the interknit wales 20. The vertical interknit 20 may be accomplished in any suitable way along spaced wales by raising and lowering a plurality of circumferentially spaced cylinder needles 52 during the rotation, of the cam ring which raises and lowers the cylinder needles, as Will be obvious to those skilled in the art. More particularly, it is preferred to provide cylinder needl-es, some of which have short butts and some of which have long butts, the former being activated by the usual stitch cam of the cam ring for knitting the single layer and the latter being the needles 52 which are actuated at the proper times by a stitch cam activating the long butt needle or by a pattern wheel. Preferably, as here shown, the pattern wheel 45 (Fig. 6) is arranged at the conventional angle of 45 degrees to the horizontal and, as will be readily apparent to those skilled in the art, when any circumferentially disposed slot of said wheel, which is filled with a wedge, registers with a needle to be raised, for example needle 52, said needle will be raised due to the cooperative association of said wedge filled slot of wheel 45 with the butt of the needle to be raised. Thus the vertical interknit of the layers 12 and 14 and the intermediate yarn 16 is achieved by the additional actuation of the cylinder needles by any suitable mechanism at predetermined spaced intervals to form the spacedwales 20. It will be readily understood that the dial 56 is so adjusted with respect to the cylinder 48 that the layers 12 and 14 are spaced apart suificiently to receive therebetween the intermediate yarn 16. The yarn 16 may be varied considably both in size and texture depending upon the desired properties of the finished composite fabric. To provide for directing the feed of the intermediate yarn 16 there is provided suitable guiding means 54 comprising a tube 58 extending transversely of the cylinder needles 44 and having an outlet end 60 positioned adjacent to the cylinder needles 44. The tube 58 is pivoted to the member 62 at 64 on an axis parallel to the cylinder needles 44 and there is provided a spring 66 fixed to the post 68 and extending to the tube 58 for biasing the tube outlet 60 to a position adjacent to the cylinder needles. It will thus be seen that the yarn feeds 50 are effective to feed yarn to form the layers 12 and 14 whereas the guide means 54 is effective to feed the yarn 16 for interposition between said layers. It will be noted that in the illustrated embodiment of a circular knitting machine as shown in Fig. 6 that the guide means for the intermediate yarn 16 is movable relative to the cylinder 43 and it will be readily understood that there will be as many intermediate yarn feeds or guides as may be desired to provide for the desired number of lengths 16 interposed between the adjacent interknit courses 18. It will be seen from the above that the method of making the composite knit fabric 10 comprises simultaneously knitting two layers of fabric in face-to-face relation on circular knitting machines 11 having cylinder needles 44 and dial needles 46, periodically activating both said cylinder and dial needles simultaneously with separate activation of said dial and cylinder needles between the above referred to periodical simultaneous activation of the needles to interknit the layers 12 and 14 along spaced courses 18, and periodically i-nterknitting the two layers 12 and 14 along spaced wales to form a multiplicity of pockets 22 in the fabric, and interposing lengths of yarn 16 between said layers in intermediate relation to a plurality of successive wales simultaneously with the interknitting of the two layers 12 and 14 and simultaneously with the interknitting of said two layers so that the interposed yarn 16 is simultaneously interknit with the layers at spaced wales 20 to form the composite knit fabric 10 shown in Fig. 4. To obtain a composition knit fabric having puckered or wrinkled air pockets 22 it is only necessary to select an intermediate yarn 16 having the desired shrinking properties as described in detail above.

The entire process of interknitting the yarn 16 between the layers 12 and 14 and interknitting the various layers is accomplished in a single operation on the knitting machine 11, which single operation produces superior composite fabric which is manifestly cheaper to manufacture. Both the amount and direction of flexibility can be varied depending on the yarn or fabric selected. By using a combination of cotton fabric for the layers 12 and 14 and wool as the intermediate yarn 16 the resultant composite knit fabric may be fabricated into garments that may be worn next to the skin since cotton normally has no maleifect to the skin of those people who may find themselves allegeric to wool.

The above described method and apparatus produces a composite knit fabric comprising two layers of fabric having therebetween an intermediate yarn with said yarn and layers secured together by interknitting and with the layers being interknit along the courses and the wales to form a plurality of pockets so that the composite fabric produced provides for the maximum of insulation and warmth with a minimum of weight and bulk. The improved composite fabric is provided with a plurality of air pockets and is economical to manufacture, extremely flexible and strong, and which possesses unusual insulating properties thereby providing a fabric having a multitude of uses for wearing apparel as well as for many other applications. If desired, a suitable metallic yarn, or wires 17 to provide an electric heating element may be laid in in the aforedescribed knitting process together with non-metallic yarn as shown in Fig. 8. If the composite fabric is provided with such laid-in metallic yarn 17 and is fabricated into a garment dry cells may be removably inserted in the pockets of the garment to serve as a self-contained source of electricity. When the metal wires or yarn 17 are incorporated in the fabric, it will ordinarily be sufiicient to lay in one length of such wire between the adjacent interknit courses, along with a suitable number of lengths of non-metallic yarn 16. Said wire 17 may be insulated thin rubber covered wire so as not to interfere with the flexibility or foldability or drapability of the fabric.

'It will be understood that various changes in the details of the fabric and in the method of making it and changes in the details of the intermediate yarn guide may be made without departing from the underlying idea of the invention within the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent, is:

l. A composite knit fabric, comprising two layers of knit fabric disposed in face-to-face relation and a plurality of lengths of yarn interposed between said layers in laterally adjacent relation and extending longitudinally of and between courses of said fabric layers in interposed relation to a series of loops of said courses of the two layers, said two layers being interknit along spaced courses, each of said lengths of yarn having longitudinally spaced portions thereof interknit with certain of the loops of said courses of the two layers.

2. A composite knit fabric, comprising two layers of knit fabric disposed in face-to-face relation and a plurality of lengths of yarn interposed between said layers and extending longitudinally of and between courses of said fabric layers in interposed relation to a series of loops of said courses of the two layers, each of said lengths of yarn having longitudinally spaced portions thereof interknit with certain of the loops of said courses of the two layers, said layers being interknit along spaced courses and along laterally spaced wales forming pockets defined at two side edges thereof by portions of said interknit courses, respectively, and at two side edges thereof at right angles to said first mentioned edges by portions of the two layers at said laterally spaced interknit wales, respectively, said lengths of yarn having portions disposed in said pockets.

3. A composite knit fabric, comprising two layers of knit fabric disposed in face-to-face relation and a plurality of lengths of yarn interposed between said layers and extending longitudinally of and between courses of said fabric layers in interposed relation to a series of loops of said courses of the two layers, each of said lengths of yarn having longitudinally spaced portions thereof interknit with certain of the loops of said courses of the two layers, said interposed intermediary yarn being more shrinkable than the yarn of at least one of said layers.

4. A composite knit fabric, comprising two layers of knit fabric disposed in face-to-face relation and a plurality of lengths of yarn interposed between said layers and extending longitudinally of and between courses of said fabric layers in interposed relation to a series of loops of said courses of the two layers, each of said lengths of yarn having longitudinally spaced portions thereof interknit with certain of the loops of said courses of the two layers, said layers being interknit along spaced courses and along laterally spaced wales forming pockets defined at two side edges thereof by portions of said interknit courses, respectively, and at two side edges thereof at right angles to said first mentioned edges by portions of the two layers at said laterally spaced interknit wales, respectively, said lengths of yarn having portions disposed in said pockets, said interposed intermediate yarn being more shrinkable than the yarn of at least one of said layers.

5. A composite knit fabric, comprising two layers of knit fabric disposed in face-to-face relation, said two layers being interknit along spaced courses and along laterally spaced wales defining a multiplicity of pockets having opposite sides of knit fabric which are free from direct connection to each other except at said spaced interknit courses and said spaced interknit wales, and lengths of intermediate yarn interposed between said sides of said pockets substantially parallel to said courses and interknit with the fabric at said spaced wales.

6. A composite knit fabric, comprising two layers of knit fabric disposed in face-to-face relation, said two layers being interknit along spaced courses and along laterally spaced wales defining a multiplicity of pockets having opposite sides of knit fabric which are free from direct connection to each other except at said spaced interknit courses and said spaced interknit wales, and lengths of intermediate yarn interposed between said sides of said pockets substantially parallel to said courses, and interknit with the fabric at said wales, said intermediate yarn being more shrinkable than said two layers in the direction of said courses whereby the opposite sides of said pockets are adapted to be puckered or wrinkled by the greater shrinkage of said interposed yarn,

7. The method of making a composite knit fabric comprising two layers of fabric having lengths of yarn interposed therebetween which comprises the steps of knitting yarn to form two layers of fabric simultaneously in face-to-face relation, interknitting the loops of the two layers along spaced courses, and interknitting the loops of the two layers along spaced wales forming a multiplicity of pockets having opposite sides of knit fabric which are free from direct connection to each other except at said spaced interknit courses and said spaced interknit wales, and interposing lengths of yarn between said layers in intermediate relation to a plurality of successive wales simultaneously with said knitting of said two layers and simultaneously with said interknitting of said two layers so that said interposed yarn is simultaneously interknit with the fabric at said spaced wales.

8. The method of making a composite knit fabric comprising two layers of fabric having lengths of yarn interposed therebetween which comprises the steps of knitting yarn to form two layers of fabric simultaneously in face-to-face relation, interknitting the loops of the two layers along spaced courses, and interknitting the loops of the two layers along spaced wales forming a multiplicity of pockets having opposite sides of knit fabric which are free from direct connection to each other except at said spaced interknit courses and said spaced interknit wales, and interposing lengths of yarn which is more shrinkable than the yarn of at least one of said layers, between said layers in intermediate relation to a plurality of successive wales simultaneously with said knitting of said two layers and simultaneously with said interknitting of said two layers so that said interposed yarn is simultaneously interknit with the fabric at said spaced wales, and treating the composite knit fabric to shrink the same and thereby pucker the opposite sides of said pockets.

9. The method of making a composite knit fabric which comprises simultaneously knitting two layers of fabric in face-to-face relation on a circular knitting machine having cylinder needles and dial needles periodically activating both cylinder and dial needles, simultaneously with separate activation of the dial and cylinder needles, respectively, between said periodical simultaneous activations of the needles, whereby to interknit said layers along spaced courses, and periodically interknitting said two layers along spaced wales whereby to form a multiplicity of pockets in the fabric.

10. The method of making a composite knit fabric comprising two layers of fabric having lengths of yarn interposed therebetween which comprises the steps of knitting yarn to form two layers of fabric simultaneously in face-to-face relation on a circular knitting machine having cylinder needles and dial needles, periodically activating both cylinder and dial needles simultaneously with separate activation of the dial and cylinder needles, respectively, between said periodical simultaneous activations of the needles, whereby to interknit said layers along spaced courses, and periodically interknitting said two layers along spaced wales whereby to form a multiplicity of pockets in the fabric, and interposing lengths of yarn between said layers in interposed relation to a plurality of successive wales simultaneously with said knitting of said two layers so that said interposed yarn is simultaneously interknit with the fabric at said spaced wales.

ll. In a circular knitting machine having cylinder needles and dial needles and yarn feed means for supplying yarn to said cylinder and dial needles for knitting two layers of fabric simultaneously, means for supplying additional yarn for interposition between said knit layers substantially parallel to the courses thereof, comprising guide means directing the feed of said yarn transversely of said cylinder needles, in position to be engaged by certain of the cylinder needles when the latter and certain of the dial needles are simultaneously activated for interknitting the two layers along spaced wales, and means for simultaneously activating the cylinder needles and dial needles for interknitting said two layers.

12. In a knitting machine having two needle beds and yarn feed means for supplying yarn to said needles on said needle beds for knitting two layers of fabric simultaneously, means for supplying additional yarn for interposition between said knit layers substantially parallel to the courses thereof, comprising guide means directing the feed of said yarn transversely of the needles of one needle bed, in position to be engaged by certain of the needles of said one bed when the latter and certain of the needles of the other bed are simultaneously activated for interknitting the two layers along spaced wales, said guide means comprising a tube extending transversely of the needles of one needle bed and having an outlet end positioned adjacent one of said needles, and means for simultaneously activating the cylinder needles and dial needles for interknitting said two layers.

13. In a circular knitting machine having cylinder needles and dial needles and yarn feed means for supplying yarn to said cylinder and dial needles for knitting two layers of fabric simultaneously, means for supplying additional yarn for interposition between said knit layers substantially parallel to the courses thereof, comprising guide means directing the feed of said yarn transversely of said cylinder needles, in position to be engaged by certain of the cylinder needles when the latter and certain of the dial needles are simultaneously activated for interknitting the two layers along spaced wales, said guide means comprising a tube extending transversely of the cylinder needles and having an outlet end positioned adjacent one of said needles, said tube being pivoted on an axis parallel to the cylinder needles and resilient means for biasing said tube outlet to said position thereof, and means for simultaneously activating the cylinder needles and dial needles for interknitting said two layers.

14. A composite fabric, comprising individual fabric layers disposed in face-to-face relation and lengths of intermediary yarn disposed between said fabric layers in interposed relation thereto, said individual layers being directly interconnected at portions thereof by integral portions thereof, respectively, along first pairs of spaced parallel lines and along other pairs of parallel lines transversely of the lines of said first pairs forming a multiplicity of pockets in the fabric defined, respectively, by confronting portions of said layers, said intermediary yarn being disposed in said pockets and secured between said layers by certain of the said interconnected portions thereof.

15. A composite fabric, comprising individual fabric layers disposed in face-to-face relation and lengths of intermediary yarn disposed between said fabric layers in interposed relation thereto, said individual layers being directly interconnected at portions thereof by integral portions thereof, respectively, along first pairs of spaced parallel lines and along other pairs of parallel lines transversely of the lines of said first pairs forming a multiplicity of pockets in the fabric defined, respectively, by confronting portions of said layers, said intermediate yarn being disposed in said pockets and secured between said layers by certain of the said interconnected portions thereof, said intermediate yarn being shrinkable to a greater degree than at least one of said layers so that shrinkage of said intermediate yarn is effective to pucker or crinkle the fabric of at least one side of said pockets.

16. A composite fabric, comprising individual fabric layers disposed in confronting face-to-face relation and having an electric heating element formed of metal interposed between said layers, said individual fabric layers being directly interconnected with each other along spaced lines by integral portions of the layers and said electric heating element being held in place between said layers by said interconnected portion I 17. A composite fabric, comprising individual fabric layers disposed in confronting face-to-face relation and having an electric heating element formed of insulated metallic wire interposed between said layers, said individual fabric layers being directly interconnected with each other along spaced lines by integral portions of the layers and said electric heating element being held in place between said layers by said interconnected portions, said layers Comprising knit fabric layers, respectively, and said interconnection of the layers comprising loops of one of said layers interknit with loops of the confronting layer.

18. A composite knit fabric, comprising two layers of knit fabric disposed in face-to-face relation and a plurality of lengths of yarn interposed between said layers and extending longitudinally of and between courses of said fabric layers in interposed relation to a series of loops of said courses of the two layers, each of said lengths of yarn having longitudinally spaced portions thereof interknit with certain of the loops of said courses of the two layers, said layers bein interknit along spaced courses and along laterally spaced wales forming a plurality of closed pockets, two side edges of each of said pockets being defined by portions of said interknit courses, respectively, and two side edges of each of said pockets extending substantially perpendicular to said first mentioned two side edges defined by portions of the two layers at said interknit wales, respectively, said lengths of yarn having portions disposed in said pockets, the latter extending in rows along two axes perpendicular to each other.

19. A com osite knit fabric, comprising twolayers of knit fabric disposed in face-to-face relation and a plurality of lengths of yarn interposed between said layers and extending longitudinally of and between courses of said fabric layers in interposed relation to a series of loops of said courses of the two layers, each of said lengths of yarn having longitudinally spaced portions thereof interknit with uniformly spaced loops of said courses of the two layers, said layers being interknit along spaced courses and along laterally spaced wales forming a plurality of closed pockets extending in aligned rows along said spaced courses and wales. an adjacent pair of spaced courses defining two side edges of a first row of pockets and an adjacent pair of spaced wales defining two sides edges of a second row of pockets e tending perpendicular to said first row of pockets, each of said pockets having opposite sides of knit fabric which are free from direct connection to each other except at said spaced interknit courses and wales, said lengths of yarn having portions disposed in said pockets, said i terposed intermediate yarn being more shrinkable than the yarn of at least one of said layers so that shrinkage of said intermediate yarn is effective to pucker or crinkle the opposite sides of said pockets.

20. The method of making a composite knit fabr comprising two layers of fabric having lengths of yarn interposed therebetween which comprises the steps of knitting yarn to form two layers of fabric simultaneously in face-to-face relation, interknitting the loops of the two layers along uniformly spaced courses, and interknitting the loops of the two layers along uniformly spaced wales to form a multiplicity of closed pockets extending in aligned rows along two axes perpendicular to each other, said pockets having opposite sides of knit fabric which are free from direct connection to each other except at said spaced interknit courses and said spaced interknit wales, and interposing lengths of yarn between said layers in intermediate relation to a plurality of successive wales simultaneously with said knitting of said two layers and simultaneously with said interknitting of said two layers so that said interposed yarn is simultaneously interknit with the fabric at said spaced rows of wales.

21. The method of making a composite knit fabric comprising two layers of fabric having lengths of yarn interposed therebetween which comprises the steps of knitting yarn to form two layers of fabric simultaneously in face-to-face relation, interknitting the loops of the two layers along uniformly spaced courses, and interknitting the loops of the two layers along uniformly spaced wales to form a multiplicity of closed pockets extending in aligned rows along two axes perpendicular to each other, said pockets having opposite sides of knit fabric which are free from direct connection to each other except at said spaced interknit courses and said spaced interknit wales, and interposing lengths of yarn which is more shrinkable than the yarn of at least one of said layers, between said layers in intermediate relation to a plurality of successive wales simultaneously with said knitting of said two layers and simultaneously with said interknitting of said two layers so that said interposed yarn is simultaneously interknit with the fabric at said spaced wales, and treating the composite knit fabric to shrink the same and thereby pucker the opposite sides of said pocke s.

22. A composite knit fabric, comprising two layers of knit fabric disposed in face-to-face relation and a plurality of lengths of yarn interposed between said layers in laterally adjacent relation, said two layers being interknit at portions thereof along spaced parallel lines, each of said lengths of yarn having longitudinally spaced portions thereof interknit between said layers at certain of the said interknit portions thereof.

23. A composite fabric, comprising individual fabric layers disposed in face-to-face relation and lengths of intermediary yarn disposed between said fabric layers in interposed relation thereto, said individual layers being directly interconnected at portions thereof by integral portions thereof, respectively, along spaced parallel lines, said intermediary yarn being secured between said layers by certain of the said interconnected portions thereof.

24. A composite knit fabric, comprising two layers of knit fabric formed of yarn of a certain thickness, said layers being disposed in face-to-face relation and a plurality of lengths of yarn interposed between said layers in laterally adjacent relation, said lengths of yarn being thicker than said first mentioned yarn, said two layers being interknit at portions thereof along spaced parallel lines, each of said lengths of yarn having longitudinally spaced portions thereof interknit between said layers at certain of the said interknit portions thereof.

25. The method of making a composite knit fabric comprising two layers of fabric having lengths of yarn interposed therebetween which comprises the steps of knitting yarn to form two layers of fabric simultaneously in face-to-face relation, interknitting the loops of the two layers along spaced parallel lines, and interposing lengths of yarn between said layers simultaneously with said knitting of said two layers and simultaneously with said interknitting of said two layers so that said interposed yarn is simultaneously interknit with the fabric at said spaced parallel lines.

References Cited in the file of this patent UNITED STATES PATENTS 

